David B. Arciniegas

Emotional and Behavioral Dyscontrol After Traumatic Brain Injury

Emotional and behavioral dyscontrol are relatively common neuropsychiatric sequelae of traumatic brain injury and present substantial challenges to recovery and community participation. Among the most problematic and functionally disruptive of these types of behaviors are pathologic laughing and crying, affective lability, irritability, disinhibition, and aggression. Managing these problems effectively requires an understanding of their phenomenology, epidemiology, and clinical evaluation. This article reviews these issues and provides clinicians with brief and practical suggestions for the management of emotional and behavioral dyscontrol.

Mood Disorders After TBI

In this article, we examine the epidemiology and risk factors for the development of the most common mood disorders observed in the aftermath of TBI: depressive disorders and bipolar spectrum disorders. We describe the classification approach and diagnostic criteria proposed in the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders. We also examine the differential diagnosis of post-TBI mood disorders and describe the mainstay of the evaluation process. Finally, we place a special emphasis on the analysis of the different therapeutic options and provide guidelines for the appropriate management of these conditions.

Repeated mild traumatic brain injury produces neuroinflammation, anxiety-like behaviour and impaired spatial memory in mice

ABSTRACT Primary Objective: Repeated traumatic brain injuries (rmTBI) are frequently associated with debilitating neuropsychiatric conditions such as cognitive impairment, mood disorders, and post-traumatic stress disorder. We tested the hypothesis that repeated mild traumatic brain injury impairs spatial memory and enhances anxiety-like behaviour. Research Design: We used a between groups design using single (smTBI) or repeated (rmTBI) controlled cranial closed skull impacts to mice, compared to a control group. Methods and Procedures: We assessed the effects of smTBI and rmTBI using measures of motor performance (Rotarod Test [RT]), anxiety-like behaviour (Elevated Plus Maze [EPM] and Open Field [OF] tests), and spatial memory (Morris Water Maze [MWM]) within 12 days of the final injury. In separate groups of mice, astrocytosis and microglial activation were assessed 24 hours after the final injury using GFAP and IBA-1 immunohistochemistry. Main Outcomes and Results: RmTBI impaired spatial memory in the MWM and increased anxiety-like behaviour in the EPM and OFT. In addition, rmTBI elevated GFAP and IBA-1 immunohistochemistry throughout the mouse brain. RmTBI produced astrocytosis and microglial activation, and elicited impaired spatial memory and anxiety-like behaviour. Conclusions: rmTBI produces acute cognitive and anxiety-like disturbances associated with inflammatory changes in brain regions involved in spatial memory and anxiety.

Association between duration of lithium exposure and hippocampus/amygdala volumes in type I bipolar disorder

BACKGROUNDnPrior studies on the effects of lithium on limbic and subcortical gray matter volumes are mixed. It is possible that discrepant findings may be explained by the duration of lithium exposure. We investigated this issue in individuals with type I bipolar disorder (BP-I).nnnMETHODSnLimbic and subcortical gray matter volume was measured using FreeSurfer in 60 subjects: 15 with BP-I without prior lithium exposure [no-exposure group (NE)]; 15 with BP-I and lithium exposure <u202f24 months [short-exposure group (SE)]; 15 with BP-I and lithium exposure >u202f24 months [long-exposure group (LE)]; and 15 healthy controls (HC).nnnRESULTSnNo differences in limbic and subcortical gray matter volumes were found between LE and HC. Hippocampal and amygdalar volumes were larger bilaterally in both LE and HC when compared to NE. Amygdalar volumes were larger bilaterally in SE when compared to NE but did not differ from LE. Hippocampal volumes were smaller bilaterally in SE when compared to LE and HC but did not differ from NE. No between-group differences on subcortical gray matter or other limbic structure volumes were observed.nnnLIMITATIONSnCross-sectional design and concurrent treatment with other medications limit attribution of between-group differences to lithium exposure alone.nnnCONCLUSIONSnThe effect of lithium exposure on limbic and subcortical gray matter volumes appears to be time-dependent and relatively specific to the hippocampus and the amygdala, with short-term effects on the amygdala and long-term effects on both structures. These results support the clinical importance of long-term lithium treatment in BP-I.

Factor analysis of the everyday memory questionnaire in persons with traumatic brain injury

Abstract Objectives: To investigate the factor structure of the Everyday Memory Questionnaire (EMQ) in persons with traumatic brain injury (TBI). Method: This was a secondary analysis of baseline data from two clinical trials targeting memory impairment after TBI. Participants were 169 persons with complicated mild, moderate, or severe TBI at an average of 41 months post-injury. They completed the EMQ via clinical interview. Exploratory factor analysis was conducted using a three-factor principal axis factoring estimation method with a polychoric correlation matrix and oblique rotation. Results: The three factors accounted for 49.2% of the variance, with moderate correlations observed among the factors. The three factors appeared to represent general everyday memory (prospective and episodic), conversational memory, and spatial or action memory. The three factors added significantly to the variance in age-corrected objective learning test scores predicted by injury severity, education, and sex. Conclusions: The three factors of the EMQ are consistent with the heterogeneity of memory impairments observed after TBI. The factor scores may be used to target treatments for impaired memory and to evaluate their effectiveness.